// Copyright 2024 Vadim Kharitonovich
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package packet

import "encoding/binary"

type Retention struct {
	index uint64
}

func NewRetention(index uint64) *Retention {
	return &Retention{
		index: index,
	}
}

func (r *Retention) Serialize() []byte {
	var buf [8]byte

	binary.BigEndian.PutUint64(buf[:], r.index)
	return buf[:]
}

func (r *Retention) Index() uint64 {
	return r.index
}

func UnserializeRetentionRequestPayload(buf []byte) *Retention {
	if len(buf[RequestHeaderSize:]) < RequestRetentionPayloadSize {
		return nil
	}

	return &Retention{
		index: binary.BigEndian.Uint64(buf[RequestHeaderSize : RequestHeaderSize+BalancedEntryIndexSize]),
	}
}
